The present invention relates to an apparatus for inspecting side surfaces of tablets, which is used for carrying flat-shaped tablets in upright states with the diameter direction thereof directed in the vertical direction, photographing the tablets in the course of carrying operation, and detecting, on the basis of the images thus obtained, appearance defects on the.side surfaces, for example, adhesion of foreign matters and contamination, cracks and chips, and deformation; an apparatus for inspecting front and back surfaces of tablets, which is used for carrying the tablets in the falling-down states with the thickness direction thereof directed in the vertical direction, turning over the tablets in the course of carrying operation, photographing the tablets before and after turn-over, and detecting the above-described appearance defects on the basis of images of the front and back surfaces of the tablets obtained by photographing; and a tablet appearance inspecting apparatus for inspecting the side surfaces and front and back surfaces of tablets while carrying the tablets by using the side surface inspecting apparatus and the front and back surface inspecting apparatus.
Conventionally, appearance defects on tablets, for example, adhesion of foreign matters or contamination, cracks or chips, deformation, and printing failure have been automatically inspected by an appearance inspecting apparatus. In the case of automatically inspecting flat-shaped tablets by using such an appearance inspecting apparatus, there has been generally adopted a method of carrying the tablets in upright states with the diameter direction thereof directed in the vertical direction; photographing, in the course of carrying operation, the tablets by using a camera, thereby picking up images of the side surfaces of the tablets: changing the postures of the tablets into falling-down states with the thickness direction thereof directed in the vertical direction and carrying the tablets in the falling-down state; turning over the tablets in the course of carrying operation; photographing the tablets before and after turn-over by using a camera, thereby picking up images of the front and back surfaces of the tablets; and processing the images of the side surfaces and front and back surfaces of the tablets, thereby detecting the presence or absence of the above-described defects.
One example of such an appearance inspecting apparatus is shown in FIG. 14.
The appearance inspecting apparatus includes a tablet feed unit p1 for carrying a number of flat-shaped tablets (hereinafter, referred to simply as xe2x80x9ctabletsxe2x80x9d) stored in a hopper p11 to an inspection mechanism portion; a side surface inspecting unit p2 having a side surface inspecting drum p21 and a side surface image pickup device p22; a posture change unit p3 having a posture change drum p31; a front and back surface inspecting unit p4 having a front surface inspecting drum p41, a back surface inspecting drum p42, a front surface image pickup device p43, and a back surface image pickup device p44; a separating unit p5 having a separating drum p51, a non-defective recovery conveyor p52, and a defective recovery can p53: and a decision unit (not shown) for processing images picked up by the three image pickup devices p22, p43, and p44, and detecting the presence or absence of appearance defects. In FIG. 14, reference numerals p221, p431, and p441 designate cameras, and p222, p432, and p442 designate illuminating devices.
The appearance inspection by using the above appearance inspecting apparatus is performed in accordance with the following procedure:
(1) A number of tablets are fed at random from the hopper p11 to the tablet feed unit p1, at which the postures of the tablets are changed into upright states with the diameter direction thereof directed in the vertical direction (hereinafter, referred to as simply xe2x80x9cupright statesxe2x80x9d), and the tablets in the upright states are continuously fed from the tablet feed unit p1 to the side surface inspecting drum p21 of the side surface inspecting unit p2.
(2) The upright tablets held in holding pockets of the side surface inspecting drum p21 are carried downwardly by the rotation of the drum p21, and in the course of carrying operation, the tablets are made to rotate on their axes in the holding pockets and simultaneously photographed by the side surface image pickup device p22. In this way, images of the all-round side surfaces of the tablets are picked up by the side surface image pickup device p22.
(3) The tablets are transferred to the posture change drum p31 of the posture change unit p3, at which the upright tablets are fallen in the horizontal direction into falling-down states with the thickness direction thereof directed in the vertical direction (hereinafter, referred to simply as xe2x80x9cfalling-down statesxe2x80x9d), and the tablets in the falling-down states are delivered to the front surface inspecting drum p41 of the front and back surface inspecting unit p4.
(4) The tablets held in the falling-down states in tablet holding pockets formed in the surface of the front surface inspecting drum p41 are carried downwardly by the rotation of the drum p4l, and in the course of carrying operation, the tablets are photographed by the front surface image pickup device p43. In this way, the images of the front surfaces of the tablets are picked up by the front surface image pickup device p43.
(5) The tablets are delivered to the back surface inspecting drum p42, being turned over, and are held in the falling-down state in tablet holding pockets of the back surface inspecting drum p42. The tablets in the falling-down states are then carried downwardly by the rotation of the drum p42, and in the course of carrying operation, the tablets are photographed by the back surface image pickup device p44. In this way, the images of the back surfaces of the tablets are picked up by the back surface image pickup device p44.
(6) The tablets are transferred to the separating drum p51 of the separating unit p5, and on the basis of the inspection result obtained by processing the images of the side surfaces and front and back surfaces of the tablets, defective tablets are transferred to the defective recovery can p53, and non-defective tablets are transferred to the non-defective recovery conveyor p52 to be recovered in a recovery container xe2x80x9ccxe2x80x9d.
The above appearance inspecting apparatus, however, often fails to stably pick up images of side surfaces of tablets by the side surface inspecting unit p2.
To be more specific, the side surface inspecting drum p21 of the side surface inspecting unit p2 includes, as shown in FIG. 15, an inner cylinder p211 and an outer cylinder p212 rotatably disposed on the outer peripheral side of the inner cylinder p211. A roller p213 rotatable on its axis is disposed inside the inner cylinder p211 in a state in which the peripheral surface thereof is exposed to the outer peripheral surface of the inner cylinder p211 through a through-window provided in the inner cylinder p211. On the other hand, as shown in FIG. 16, a number of through-hole shaped holding pockets p214 are aligned in the peripheral surface of the outer cylinder p212. The pickup of an image of the side surface of each tablet is performed by the side surface inspecting unit p2 as follows: namely, as shown in FIG. 15, the tablet xe2x80x9ctxe2x80x9d held in the upright state in the holding pocket p214 of the outer cylinder p212 is carried by intermittent rotation of the outer cylinder p212 while rolling on the outer peripheral surface of the inner cylinder p211; and when carried on the roller p213 rotating on its axis and intermittently stopped, the tablet xe2x80x9ctxe2x80x9d rotates on its axis in the state being stopped in the upright posture by the rotation of the roller p213, and in such a state, the tablet xe2x80x9ctxe2x80x9d is photographed by the image pickup device p22.
In this case, when carried on the roller p213 by the rotation of the outer cylinder p212, the tablet xe2x80x9ctxe2x80x9d rolling on the inner peripheral surface of the inner cylinder p211 is raised on the roller p213 projecting from the outer peripheral surface of the inner cylinder p211, and in such a state, the tablet xe2x80x9ctxe2x80x9d rotates on their axes by the rotation of the roller p213. As a result, the posture of the tablet xe2x80x9ctxe2x80x9d upon rotation thereof on its axis is unstable, tending to cause an inconvenience that the tablet xe2x80x9ctxe2x80x9d is not necessarily allowed to stably rotate on its axis. Further, since the tablet xe2x80x9ctxe2x80x9d having slowly rolled on the fixed inner cylinder p211 is suddenly landed on the roller p213 rotating on its axis at a high speed and is rapidly rotated by the rotation of the roller p213 at a high speed, it takes a slight time until the rotation of the tablet xe2x80x9ctxe2x80x9d on its axis becomes stable, and since the tablet xe2x80x9ctxe2x80x9d rotates on its axis while rolling on the small-sized roller p213 rotating on its axis at a high speed, the tablet xe2x80x9ctxe2x80x9d may be slightly jumped from the roller p213, thereby making it difficult for the table xe2x80x9ctxe2x80x9d to rotate on its axis while keeping its stable posture.
The prior art tablet appearance inspecting apparatus, therefore, is not easy to obtain a clear image of the side surface of the tablet xe2x80x9ctxe2x80x9d which rotates on its axis as described.
Another problem of the prior art tablet appearance inspecting apparatus will be described below. According to the prior art apparatus, the posture of the tablet xe2x80x9ctxe2x80x9d is changed by a manner of feeding the tablet xe2x80x9ctxe2x80x9d in an upright state from the side surface inspecting drum p21 in a posture change pocket formed in the outer peripheral surface of the posture change drum p31; and making the tablet xe2x80x9ctxe2x80x9d fall down by a guide plate to change the posture of the tablet xe2x80x9ctxe2x80x9d from the upright state to a falling-down state in the course of carrying operation by the rotation of the posture change drum p31. Accordingly, a large load or impact is applied to the tablet xe2x80x9ctxe2x80x9d upon the above-described posture change operation, with a result that the tablet xe2x80x9ctxe2x80x9d is susceptible to breakage such as cracks or chips upon the posture change thereof.
To be more specific, as shown in FIG. 17, the posture change of the tablet xe2x80x9ctxe2x80x9d by the posture change drum p31 is performed as follows: The tablet xe2x80x9ctxe2x80x9d in an upright state is fed from the side surface inspecting drum p21 into a posture change pocket p311 of the posture change drum p31, and is carried downwardly, by the rotation of the posture change drum p31, in a state in which part of the tablet xe2x80x9ctxe2x80x9d projects from the posture change pocket p311. At this time, the tablet xe2x80x9ctxe2x80x9d is prevented from being dropped from the posture pocket p311 by a guide plate P32 fixed along the outer peripheral surface of the posture change drum p31, and the projecting portion of the tablet xe2x80x9ctxe2x80x9d is made to enter an approximately V-shaped posture change groove p321 obliquely tilted with respect to the rotational direction by only an edge portion p322 provided on one side of the guide plate p32, to push sideways the projecting portion of the tablet xe2x80x9ctxe2x80x9d by the tilting edge portion p322 of the posture change groove p321, thereby pushing down the tablet xe2x80x9ctxe2x80x9d in the posture change pocket p311 to change the posture of the tablet xe2x80x9ctxe2x80x9d into a falling-down posture.
In this way, according to the prior art tablet appearance inspecting apparatus, in the course of carrying the tablet xe2x80x9ctxe2x80x9d held on the peripheral surface of the posture change drum p31 by the rotation of the posture change drum p31, the upright tablet xe2x80x9ctxe2x80x9d is slid in contact with the posture change groove p321 of the guide plate p32, to be forcibly pushed down by the tilting edge portion p322 of the posture change groove p321, and accordingly, a large load or impact is applied to the tablet xe2x80x9ctxe2x80x9d upon the posture change thereof. As a result, a relatively brittle tablet may cause breakage such as cracks or chips. Also since the tablet xe2x80x9ctxe2x80x9d must enter the posture change groove p321 while keeping a stable upright posture, if the upright posture of the tablet xe2x80x9ctxe2x80x9d is unstable, the tablet xe2x80x9ctxe2x80x9d may be jammed between the guide plate p32 and the outer peripheral surface of the posture change drum p31, with a result that the tablet xe2x80x9ctxe2x80x9d may cause cracks.
Further, the size of the posture change pocket p311 formed in the posture change drum p31 must be set at a suitable value depending on the size and shape of the tablets xe2x80x9ctxe2x80x9d for stably changing the postures of the tablets xe2x80x9ctxe2x80x9d, and accordingly, each time the kind (size or thickness) of tablets to be inspected is changed, the posture change drum p31 must be changed to the posture change drum having the posture change pocket p311 of the size corresponding to the kind of the tablets. This requires significantly complicated works to change the kind of tablets to be inspected.
An object of the present invention is to provide an apparatus for inspecting the side surfaces of tablets, which is capable of picking up images of the side surfaces of the tablets while making the tablets stably rotate on their axes in upright states, thereby easily, accurately inspecting the side surfaces of the tablets; an apparatus for inspecting front and back surfaces of tablets, which is capable of inspecting the front and back surfaces of the tablets by controlling the postures of the tablets into falling-down postures without applying large loads or impacts on the tablets; and a tablet appearance inspecting apparatus for inspecting side surfaces and front and back surfaces of tablets while carrying the tablets by using the side surface inspecting apparatus and the front and back surface inspecting apparatus.
To achieve the above object, according to the present invention, there is provided an apparatus for inspecting side surfaces of tablets, including:
an inner cylinder continuously rotatable at a specific speed;
an outer cylinder disposed on the outer peripheral side of the inner cylinder in such a manner as to be intermittently rotatable along the outer peripheral surface of the inner cylinder, the outer cylinder having in its peripheral wall a number of through-hole shaped holding pockets; and
a side surface image pickup device for photographing tablets held in the holding pockets of the outer cylinder, thereby picking up images of the side surfaces of the tablets;
wherein the inspecting apparatus inspects the side surfaces of flat-shaped tablets by holding the tablets, which are in upright states with the diameter direction thereof directed in the vertical direction, in the holding pockets of the outer cylinder intermittently rotating; carrying the tablets by the intermittent rotation of the outer cylinder while making the tablets roll on the outer peripheral surface of the inner cylinder continuously rotating; making, when the outer cylinder is intermittently stopped in the course of carrying operation, the tablets rotate on their axes in the holding pockets by the continuous rotation of the inner cylinder, and photographing the tablets by the side surface image pickup device thereby picking up images of the all-round side surfaces of the tablets; and processing the images thus obtained, thereby detecting the presence or absence of appearance defects on the side surfaces of the tablets.
That is to say, the side surface inspecting apparatus of the present invention includes the intermittent rotatable outer cylinder for carrying tablets held in the holding pockets and the continuously rotatable inner cylinder inside the outer cylinder, wherein the tablets held in the upright states in the holding pockets of the outer cylinder are carried while rolling on the outer peripheral surface of the inner cylinder by the intermittent rotation of the outer cylinder, and at a specific carrying point, the tablets rotating on their axes in the holding pockets of the intermittently stopped outer cylinder while rolling on the outer peripheral surface of the continuously rotating inner cylinder are photographed by the side surface image pickup device. In this way, the images of the side surfaces of the tablets are picked up by the side surface image pickup device.
Accordingly, even in either the carrying state or the side surface image pickup state, the tablets rotate on their axes while rolling on the outer peripheral surface of the inner cylinder. As a result, unlike the prior art apparatus in which the tablets upon photographing are made to rotate on their axes by a separately provided roller rotatable on its axis, the tablets upon photograph can be made to rotate on their axes in the same state as that upon carrying of the tablets without the occurrence of the inconvenience that the tablets are raised on the roller rotatable on its axis. Further, as compared with the prior art apparatus in which the tablets are moved from the fixed inner cylinder to the roller rotating on its axis at a high speed and thereby the rotational speed is rapidly increased, the tablets can be significantly smoothly shifted to the rotational states on their axes suitable for photographing, whereby images of the side surfaces of the tablets stably rotating on their axes can be picked up. Further, since the inner cylinder for making the tablets rotate on their axes upon photographing of the sides surfaces of the tablets has a diameter much larger than the diameter of the prior art roller rotatable on its axis, the tablets upon photographing rotate on their axes while rolling on the outer peripheral surface, which is flatter than the outer peripheral surface of the above roller, of the inner cylinder. In this regard, the rotation of the tablets on their axes becomes further stable.
In this way, according to the side surface inspecting apparatus of the present invention, as compared with the prior art apparatus characterized by making tablets roll on their axes by using the roller rotatable on their axes, it is possible to pick up images of the side surfaces of tablets while making the tablets stably rotate on their axes, and hence to certainly obtain clear images of the side surfaces of the tablets and thereby accurately inspect the side surfaces of the tablets.
To achieve the above object, according to the present invention, there is also provided an apparatus for inspecting front and back surfaces of tablets including:
a front surface inspecting drum for holding flat-shaped tablets, which are in falling-down states with the thickness direction thereof directed in the vertical direction, on the outer peripheral surface thereof, and carrying the tablets by the rotation of the drum at a specific speed;
a back surface inspecting drum, disposed in a state in which the outer peripheral surface thereof is in proximity to the outer peripheral surface of the front surface inspecting drum, for receiving the tablets from the front surface inspecting drum in a state in which the tablets are turned over, holding the tablets, which are in the falling-down states, on the outer peripheral surface thereof, and carrying the tablets by rotation of the drum at a specific speed;
a front surface image pickup device for photographing the tablets held on the outer peripheral surface of the front surface inspecting drum, thereby picking up images of the front surfaces of the tablets;
a back surface image pickup device for photographing the tablets held on the outer peripheral surface of the back surface inspecting drum, thereby picking up images of the back surfaces of the tablets; and
tablet feed unit for feeding the tablets onto the outer peripheral surface of the front surface inspecting drum, the tablet feed unit comprising: a vibration plate having tablet feed passages each having a size allowing a tablet in the falling-down state to pass therethrough, the vibration plate being tilted downwardly to the front inspecting drum by a specific angle with one end of the vibration plate positioned in proximity to the outer peripheral surface of the front surface inspecting drum; and a tablet storing portion for storing a specific amount of tablets, the tablet storing portion being provided on the other end side of the vibration plate, whereby the tablets in the tablet storing portion are continuously introduced in the tablet feed passages of the vibration plate, and the tablets thus introduced in the tablet feed passages are continuously moved, by fine vibration of the vibration plate, to the one end portion of the vibration plate and fed from the one end portion of the vibration plate onto the front surface inspecting drum;
wherein each of the front surface inspecting drum and the back surface inspecting drum includes a suction groove formed in the outer peripheral surface thereof in such a manner as to extend along the circumferential direction, a number of suction holes formed in the suction grooves in such a manner as to align in the circumferential direction, and at least a pair of rubber rings mounted on both side edge portions of the suction groove with the suction holes put therebetween, whereby the tablets are attractively held while lying astride the pair of the rubber rings by a suction force obtained by sucking the inside of the suction groove from the inside of the drum through the suction holes.
The front and back surface inspecting apparatus of the present invention is intended to attractively hold tablets in falling-down states, by suction, on the rubber rings disposed on the outer peripheral surface of the front surface inspecting drum or back surface inspecting drum; and
turn over the tablets by delivery of the tablets between the front surface inspecting drum and the back surface inspecting drum, and in the course of carrying operation, photograph the tablets on the front surface inspecting drum and the tablets on the back surface inspecting drum, to pick up images of the front and back surfaces of the tablets, thereby inspecting the front and back surfaces of the tablets. In this case, according to the apparatus of the present invention, the tablets stored in the tablet storing portion are introduced in the tablet feed passages of the vibration plate, and moved to one end portion of the vibration plate disposed in proximity to the outer peripheral surface of the front surface inspecting drum by fine vibration of the vibration plate. At this time, since each of the tablet feed passages has a size allowing a tablet in a falling-down state to pass therethrough, the tablets in the tablet feed passages are certainly allowed to be in falling-down states by vibration of the vibration plate. The tablets in the falling-down states are moved from the one end portion of the vibration plate to the front surface inspecting drum, to be thus fed on the front surface inspecting drum in the falling-down states.
Accordingly, it is not required to perform any special operation to change the postures of the tablets having been subjected to side surface inspection by the side surface inspecting drum from upright states to falling-down states, for example, by charging the non-defective tablets having no appearance defects on the side surfaces, which have been inspected by the side surface inspecting apparatus, in the tablet storing portion; feeding the tablets to the front surface inspecting drum by the vibration plate; turning over the tablets by delivery of the tablets between the front surface inspecting drum and the back surface inspecting drum and carrying the tablets thus turned over, and picking up, in the course of carrying operation, images of the side surfaces and front and back surfaces of the tablets, thereby inspecting the side surfaces and front and back surfaces of the tablets. That is to say, the front and back surfaces of tablets can be inspected only by feeding the tablets, which have been subjected to side surface inspection, in the tablet storing portion of the front surface inspecting drum.
As a result, according to the front and back surface inspecting apparatus of the present invention, as compared with the prior art apparatus characterized by inspecting front and back surfaces of tablets by forcibly changing the postures of the tablets from upright postures to falling-down postures, it is possible to certainly inspect the front and back surfaces of tablets by significantly reducing loads or impacts applied to the tablets without occurrence of cracking, chipping, or shaving.
Further, according to the front and back surface inspecting apparatus of the present invention, since tablets are attracted on the rubber rings mounted on the outer peripheral surface of the front surface inspecting drum or back surface inspecting drum to be held thereon while projecting from the outer peripheral surface of the drum, the tablets can be photographed without occurrence of any shadow on the tablets. Since the tablets are photographed in a state in which the tablets are attractively held on the surface of the drum without no gap therebetween, it is possible to certainly obtain clear images, and hence to accurately inspect the front and back surfaces of the tablets. Further, since tablets are turned over, by delivery of the tablets between the front surface inspecting drum and the back surface inspecting drum, in a state in which the tablets are put between the rubber rings on the front surface inspecting drum and the rubber rings on the back surface inspecting drum, it is possible to certainly deliver the tablets between both the drums without applying large loads to the tablets so much by the effect of the elastiticity and deflection of the rubber rings, and hence to certainly perform the delivery and turn-over works of the tablets without occurrence of breakage of the tablets.
According to the front and back surface inspecting apparatus, since tablets are carried while being attractively held between both edges of a pair of the rubber rings, even if the size of the tablets is changed, such tablets can be carried while being attractively held on the same inspecting drum with no problem. Further, since the tablets are delivered between the front surface inspecting drum and the back surface inspecting drum in a state being put between the rubber rings by making use of the elasticity and deflection of the rubber rings, even if the thickness of the tablets is changed, such tablets can be delivered between both the drums without occurrence of breakage because the change in thickness of the tablets is permitted by the elasticity and deflection of the rubber rings. As a result, the front and back surface inspecting apparatus allows a change in size of tablets to be inspected, and each of the tablet feed passages provided in the vibration plate for feeding tablets onto the front surface inspecting drum may be designed into a size which allows one row of tablets in falling-down states to pass therethrough but does not allow two rows of tables in falling-down states to pass therethrough. In other words, even if the size of the tablets is somewhat changed, the tablets can be desirably fed by using the same vibration plate. As a result, it is possible to inspect tablets different in size (diameter or thickness) without the need of changing the front surface inspecting drum, back surface inspecting drum, and vibration plate.
Here, the front and back surface inspecting apparatus of the present invention may be configured, while not particularly limited thereto, such that the tablet feed unit further includes a tablet feed roller rotatable at a desired speed, the roller being disposed at the one end of the vibration plate in such a manner as to be in contact with or in proximity to the tablet feed passages, whereby the tablets are moved from the one end portion of the vibration plate onto the front surface inspecting drum by the rotation of the tablet feed roller, to be thereby fed at a desired speed.
To be more specific, by moving the tablets from the tablet storing portion to the one end of the vibration plate via the tablet feed passages, and further moving the tablets from the one end portion of the vibration plate onto the front surface inspecting drum by the tablet feed roller, thereby feeding the tablets onto the front surface inspecting drum, the tablets can be stably fed onto the front surface inspecting drum at a specific speed corresponding to the rotational speed of the tablet feed roller. As a result, it is possible to stably inspect the front and back surfaces of the tablets.
The feed speed of the tablets onto the front surface inspecting drum can be adjusted by controlling the rotational speed of the tablet feed roller. As a result, the feed speed of the tablets can be set at an optimum value in consideration of the size of the tablets, the feed speed of the tablets in the tablet storing portion, the required processing ability, the image pickup ability, and the ability of processing the pickup image. Even in this regard, it is possible to efficiently perform the accurate, stable inspect of the front and back surfaces of tablets.
To achieve the above object, according to the present invention, there is provided a tablet appearance inspecting apparatus for inspecting the side surfaces and front and back surfaces of tablets, which includes a side surface inspecting unit composed of the above-described side surface inspecting apparatus, particularly, characterized by including a defective ejecting mechanism for selectively ejecting, in the course of carrying operation, the tablets carried while being held in the holding pockets of the outer cylinder, and a side surface defective decision unit for processing images of the side surfaces of the tablets, thereby deciding the presence or absence of appearance defects, wherein the tablets, which are decided as defective tablets each having an appearance defect on the side surface by the side surface defective decision unit, are selectively ejected from the holding pockets by the defective ejecting mechanism; and a front and back surface inspecting unit composed of the above-described front and back surface inspecting apparatus, particularly, characterized by including a defective ejecting mechanism for selectively ejecting, in the course of carrying operation, the tablets carried while being held on the outer peripheral surface of the back surface inspecting drum, and a front and back surface defective decision unit for processing images of the front and back surfaces of the tablets picked up by the front surface image pickup device and the back surface image pickup device, thereby deciding the presence or absence of appearance defects, wherein the tablets, which are decided as defective tablets each having an appearance defect on the front surface and/or back surface by the front and back surface defective decision unit, are selectively ejected from the back surface inspecting drum by the defective ejecting mechanism.
That is to say, the tablet appearance inspecting apparatus of the present invention is operated to inspect side surfaces of tablets by the side surface inspecting unit and selectively eject defective tablets each having an appearance defect on the side surface; feed all of the tablets with no defects on the side surfaces from the side surface inspecting drum into the tablet storing portion of the front and back inspecting unit; inspect front and back surfaces of the tablets by the front and back surface inspecting unit and selectively eject defective tablets each having an appearance defect on the front or back surface; and recover non-defective tablets with no appearance defects on the side surfaces and front and back surfaces from the back surface inspecting drum of the front and back surface inspecting unit.
Alternately, the tablet appearance inspecting apparatus of the present invention may be operated to feed tablets to be inspected in the tablet storing portion of the front and back surface inspecting unit; inspect the front and back surfaces of the tablets by the front and back surface inspecting unit, and selectively eject defective tablets each having an appearance defect on the front or back surface; change the postures of all of the tablets with no appearance defects on the front and back surfaces from the falling-down postures to right postures, and feed the tablets from the back surface inspecting drum of the front and back surface inspecting unit onto the side surface inspecting drum of the side surface inspecting unit; inspect the side surfaces of the tablets by the side surface inspecting unit and selectively eject defective tablets each having an appearance defect on the side surface; and recover non-defective tablets with no appearance defects on the side surfaces and front and back surfaces from the side surface inspecting drum of the side surface inspecting unit.
According to the above-described tablet appearance inspecting apparatus, it is possible to pick up images of the side surfaces of tables while making the tablets stably rotate on their axes in upright states and thereby certainly, accurately inspect the side surfaces of the tablets on the basis of the clear images of the side surfaces of the tablets, to inspect the front and back surfaces of the tablets in falling-down states without applying large loads or impacts to the tablets and thereby certainly inspect the front and back surfaces of the tablets without occurrence of breakage of the tablets, and to inspect tablets different in size (diameter or thickness) without the need of changing the front surface inspecting drum, back surface inspecting drum, and vibration plate of the front and back surface inspecting unit.
In the case of the inspecting operation of inspecting the front and back surfaces of tablets by the front and back surface inspecting unit, ejecting defective tablets having appearance defects on the front and back surfaces, inspecting the side surfaces of non-detective tablets with no appearance defects on the front and back surfaces, and ejecting defective tablets with appearance defects on the side surfaces, it is possible to eject the defective tablets being deformed by cracks or chips by the initial front and back surface inspection, and hence to certainly prevent the occurrence of an inconvenience that the tablets thus deformed are jammed in the holding pockets of the side surface inspecting drum upon side surface inspection by the side surface inspecting unit. This makes it possible to stably inspect the appearances of tablets.